Abstract: This research intends to offer the first Portuguese translation of Francesco Petrarch¿s Latin work Invective contra medicum, followed by notes from a study about the text, and two appendices that comprise the translation of the preface written by the Paris¿ bishop at the time, Etienne Tempier, to the Condemnation Syllabus of 1277, and the translation of some articles mentioned by Petrarch in these invectives. The introductory study, named The man and the dog, proposes an interpretation of the physician¿s ethical construction and, consequently, of the poet¿s ethos itself, defined in opposition to his adversary¿s character. From the physician¿s characterization, Petrarch attacks the aristotelism of the art masters of Paris, restates the value of a Christian moral wisdom founded on a philosophical usage of defining philosophy as meditation about death, and establishes himself as a virtue model